This invention relates in general to an engine, and in particular to such an engine having an orbital piston and mating cylinder which alternately transmit energy to a central crank.
With the steadily decreasing availability of energy sources, particularly liquid hydrocarbon fuels such as gasoline, it has become increasingly desirable to develop small, low powered, low speed internal combustion engines which are efficient. Rotary engines have been used frequently in the past for this purpose since maximum torque is delivered to the crank during the entire firing portion of their operation cycle. Rotary engines have been used as a replacement for reciprocating internal combustion engines, which, due to the eccentric connection of the connecting rod to the crank, provide low torque at the initiation of the stroke when the crank presents little lever arm to the connecting rod.
The prior art rotary engines generally combine an irregularly shaped rotor rotatably enclosed in a mating housing which defines several isolated combustion chambers. Since these rotors are of the continuous rotation type, they are difficult to seal against loss of combustion gases, thus causing excess emissions of unburned hydrocarbons. In addition the seals are subject to unsymmetrical loading causing rapid wear necessitating frequent, expensive replacement.
Accordingly, it is the general purpose of the present invention to provide a rotary engine utilizing an arcuate cylinder and an enclosed sealed piston which alternately move in a common direction around a central crank transmitting force to the crank through a lever arm having a length which is independent of piston displacement, by means of connecting rods which remain normal to the applied force at all times.
It is a further purpose of the present invention to provide such an engine having simple, low cost valve means and valve timing means configured for positive operation.
It is a further purpose of the present invention to provide a positive escapement means in such an engine imparting rotary movement of the piston and cylinder in a first direction to a central crank and preventing their movement in the opposite direction.